This invention relates generally to controller apparatus used to produce a timed sequence of operations and more particularly to a drive mechanism therefor. Specifically, the present invention relates to a water powered drive means for operating an automatic controller apparatus, such as an irrigation control apparatus having a camming means mounted upon a camming shaft for engaging a plurality of control arms which in turn operate pilot valves associated with pilot operated water valves in an irrigation or watering system.
An automatic irrigation control apparatus is shown in U.S. Pat. No. 2,821,434 of which I am a co-inventor, the disclosure of said U.S. Pat. No. 2,821,434 being incorporated herein by its reference. Generally stated, however, the automatic irrigation control apparatus of the aforesaid patent includes a bank of pilot water valves operated by a series of control levers, camming means for operating the levers, an electric motor drive means, generally a constant speed clock-type motor, and transmission and clutch means for selectively connecting the caming means to the constantly running motor drive means. As a cam on the caming means interferes with an associated control lever of this prior control apparatus, the control apparatus opened an associated pilot valve to allow water flow to a pilot operated water valve in a selected area of an irrigation system to initiate a watering or sprinkling operation therein. A timing or watering cycle therefor continued during the constant speed driving of the cam past a cam follower portion provided in the control lever, the length of the watering or sprinkling operation being adjustable through movement of the control lever. However, in this prior controller, as in other similar controllers heretofore available, the constant speed, clock-type motor has comprised an electric motor requiring electrical connections and, of course, a source of electric power.
In many installations of automatic irrigation control devices, for example, the control device is preferably located where it is convenient to connect it to the water lines of the irrigation or sprinkling system. Such location is frequently remote from a source of electric power and special electrical provisions must be made for installation of the controller. Further, the use of an electric motor drive for a controller apparatus requires various safety precautions be taken in the overall construction and operation of the device in order to minimize hazards accompanying the use of electrical power in association with water handling equipment.
It is therefore the primary object of the present invention to disclose and provide a water powered drive means for an automatic control apparatus.
It is another object of the present invention to disclose and provide a drive means for an automatic irrigation control apparatus which is powered by the water pressure normally available for operating sprinkling and watering devices in the irrigation system being controlled.
It is a still further object of the present invention to disclose and provide a water powered drive means for an automatic controller apparatus which drives such apparatus at a constant speed, as a clock-type electric motor would, without the need for electrical connections or electrical power.